1. Field of the Invention
The present invention relates to a process for production of a pyrrolidinone compound which is useful as, for example, a remedy for central nervous system disorders (e.g. schizophrenia, dementia, manic depressive psychosis, anxiety neurosis, drug poisoning and ischemic encephtalopathy), diseases associated with immunodeficiency and cryptorrhea, peptic ulcer, diabetes and complications thereof, glaucoma, etc.; a 3-carboxy-1-substituted-2-pyrrolidinone compound which is a useful intermediate for production of the above pyrrolidinone compound; and a process for production of the 3-carboxy-1-substituted-2-pyrrolidinone compound.
2. Description of the Related Art
Pyrrolidinone compounds having a pyrrolidinone skeleton as the basic structure, which are useful as, for example, a remedy for central nervous system disorders (e.g. schizophrenia, dementia, manic depressive psychosis, anxiety neurosis, drug poisoning and ischemic encephtalopathy), diseases associated with immunodeficiency and cryptorrhea, peptic ulcer, diabetes and complications thereof, glaucoma, etc., and processes for production of the compounds are disclosed in EP Publication No. 0668275A1 and Japanese Patent Application Kokai (Laid-Open) No. 40667/1997.
In producing the pyrrolidinone compounds according to the above processes, however, the number of steps is large and a reduction in the number of steps has been desired for the economic reason. There has also been a problem of using a hydrogen-generating substance. There has also been a problem that a corrosive substance must be used.
With respect to the process for production of a 3-carboxy-1-phenyl-2-pyrrolidinone compound which is useful as an intermediate for production of the above pyrrolidinone compounds, there are known, for example, a process by Danishefsky et al. described in Org. Synth., 60, 66-71, 1981; and a process of hydrolyzing an ester compound obtained by a process described in Japanese Patent Application Kokai (Laid-Open) No. 40667/1997.
However, the former process uses, as a raw material, 6,6-dimethyl-5,7-dioxaspiro[2.5]octane-4,8-dione which is expensive. Also, the latter process of hydrolyzing an ester compound is not preferred for a safety reason because it may use a moisture sensitive/ignitive reagent in synthesis of the ester compound. None of these processes is satisfactory for industrial application.